The instant invention pertains to vacuum cleaners and in particular to coin operated, commercial vacuum cleaner canisters and the coin mechanisms associated therewith.
Car wash facilities for consumer automobiles have typically included some provision for self service use of vacuum cleaning apparatus. Such devices have recently become revenue production devices with the inclusion of coin mechanisms to provide means for charging for use of the vacuum cleaning device. The proliferation of so-called "convenience" stores has also increased the demand for vacuum cleaning machines available to the public for use in cleaning interiors of motor vehicles of all kinds. Particularly in the setting of a "convenience" store, a coin-operated, self-service vacuum cleaner is desirable.
Existing vacuum cleaners are frequently made from sheet steel rolled into a cylindrical canister with a top and bottom. The vacuum motor works upon the cavity of the canister to create a reduced air pressure therein in order to effect the desired suction within hoses styled to communicate with the canister's interior. Coin mechanisms are usually welded to the outside of the canister in order to make them convenient to the user and for appropriate connection to control the vacuum cleaning device. However, with the coin mechanism mounted to the outer surface of the canister, the security of the coin device is at risk due to the access to a thief or vandal to much of the outside of the body of the coin mechanism.
Additionally, with the coin mechanism mounted to the exterior of the canister, the most feasible location for a receptacle to collect coins inserted in the coin mechanism is within the coin mechanism itself.
Earlier attempts at providing a coin mechanism which does not extend from the outside of the canister body have been thwarted by difficulty in feasibly and economically mounting the coin box within a recess in the canister sidewall. It is well known that the rolling of a sheet metal blank having a rectangular opening therein results in a cylindrical body which no longer has a true rectangular opening. Discontinuities in the roll develop surrounding the opening. Tedious and expensive welding measures are necessary to successfully mount the coin mechanism into the nonrectangular opening. Unless a non-standardized coin mechanism having a curved front panel were developed to be used, an uneven and displeasing weldment results, additionally suffering from a tendency to allow air leakage at the welds.